Apparatus for the open-end spinning of textile yarns

ABSTRACT

Open-end spinning apparatus in which twisted yarn is formed by continuously depositing discrete fibers on a fiber collecting surface of a spinning rotor, continuously removing them from the surface to form the tail end of a yarn and drawing off the continuously formed twisted yarn, said spinning rotor having an inner surface which is concentric with respect to the rotary axis of the rotor and which has two portions converging toward a region of maximum diameter at which said fiber collecting surface is located and said apparatus further comprising a yarn delivery tube extending from a yarn outlet end across a plane in which lie the points of maximum diameter of the fiber collecting surface and terminating at a yarn inlet end within the spinning rotor, said yarn delivery tube being provided at said yarn inlet end with a flange having a surface which extends outwardly and back toward said fiber collecting surface to form a guide surface for fibers being spun into yarn while being withdrawn from the fiber collecting surface, and a rear surface opposite said front guide surface and confronting said closure surface and said fiber feed duct exit opening.

United States Patent 1191 Croasdale et al.

1 51 Oct. 29, 1974 APPARATUS FOR THE OPEN-END SPINNING OF TEXTILE YARNS [75] Inventors: Fred Croasdale, Whalley; Michael John English, l-lelmshore, both of England [73] Assignee: Platt International Limited, Oldham,

England [22] Filed: Oct. 18, 1972 [21] Appl. No.: 298,544

[30]. Foreign Application Priority Data Oct. 19, 1971 Great Britain 48542/71 [52] US. Cl. 57/58.89 [51] Int. Cl D01h l/l2 [58] Field of Search 57/58.8958.95

[56] References Cited UNITED STATES PATENTS 3,447,298 6/1969 Collins 57/58.89 3,481,128 12/1969 Landwehrkamp et a1. 57/58.89 3,501,905 3/1970 Landwehrkamp et al. 57/58.89 3,640,061 2/1972 Landwehrkamp 57/58.89

Primary Examiner.lohn Petrakes [5 7] ABSTRACT Open-end spinning apparatus in which twisted yarn is formed by continuously depositing discrete fibers on a fiber collecting surface of a spinning rotor, continuously removing them from the surface to form the tail end of a yarn and drawing off the continuously formed twisted yarn, said spinning rotor having an inner surface which is concentric with respect to the rotary axis of the rotor and which has two portions converging toward a region of maximum diameter at which said fiber collecting surface is located and said apparatus further comprising a yarn delivery tube extending from a yarn outlet end across a plane in which lie the points of maximum diameter of the fiber collecting surface and terminating at a yarn inlet end within the spinning rotor, said yarn delivery tube being provided at said yarn inlet end with a flange having a surface which extends outwardly and back toward said fiber collecting surface to form a guide surface for fibers being spun into yarn while being withdrawn from the fiber collecting surface, and a rear surface opposite said front guide surface and confronting said closure surface and said fiber feed duct exit opening.

14 Claims, 2 Drawing Figures PATENTED 00129 I974 WEE-I 10F 2 m m num 29 1914 3844 100 sum 2 or 2 APPARATUS FOR THE OPEN-END SPINNING OF TEXTILE YARNS to exercise close control over the yarn immediately after it has been formed.

It is an object of the present invention to provide open-end spinning apparatus of the type specified, which is conducive to the production of an open-end spun yam'at high production rates.

According to the present invention, there is provided open-end spinning apparatus in which twisted yarn is formed by continuously depositing discrete fibres on a fibre collecting surface of a spinning rotor, continuously removing them from the surface to form the tail end of a yarn and drawing off the continuously formed twisted yarn, said spinning rotor having an inner surface which is concentric with respect to the rotary axis of the rotor and which has two portions converging toward a region of maximum diameter at which said fibre collecting surface is located and said apparatus further comprising a yarn delivery tube extending from a yarn outlet end across a plane in which lie the points of maximum diameter of the fiber collecting surface and terminating at a yarn inlet end within the spinning rotor, said yarn delivery tube being provided at said yarn inlet end with a flange having a surface which extends outwardly and back toward said fibre collecting surface to form a guide surface for fibres being spun into yarn whilst being withdrawn from the fibre collecting surface.

Preferably, the yarn delivery tube is so arranged as to be coaxial with the rotary axis of the spinning rotor and preferably the yarn delivery tube at the yarn inlet end has a flared throat portion leading to said guide surface. A plurality of grooves may be formed in the throat portron.

Two embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which:

FIG. 1 is a schematic cross-section through open-end spinning apparatus according to a first embodiment of the invention, and

FIG. 2 is a cross-section of open-end spinning apparatus according to a second embodiment of the inventron.

Referring first to FIG. 1 of the drawings, a spinning rotor l is fixedly mounted on a rotor driving shaft 2 rotatably supported in a bearing assembly (not shown). The rotor l is arranged within a cavity 3 of a rotor housing 4 to which suction is applied through a suction duct 5. The spinning rotor l is open at the top and closed at the bottom and has an inner surface concentric with respect to the rotary axis of the rotor. A frusto-conical upper portion 6 of the surface extends downwardly and outwardly from the top of the rotor and a frusto-conical lower portion 7 of the surface extends upwardly and outwardly from the bottom of the rotor,

the two portions 6 and 7 converging to provide a region of maximum diameter. At the region of maximum diameter there is formed a fibre collecting groove 8 concentric with respect to the rotary axis of the spinning rotor l.

A closure member 9 for the cavity 3 has a cylindrical portion 10 depending centrally from its underside into the vicinity of the open top of the spinning rotor 1. Supported by the closure member 9 is a fibre feed tube 11, which passes through the closure member and opens into a frusto-conical bottom surface 12 of the closure member 9. Extending centrally through the closure member 9 is a'yarn delivery tube 13 coaxial with the rotary axis of the spinning rotor l. The yarn delivery tube 13 terminates within the rotor in a yarn inlet end where it is formed with a separator flange 17.

The flange 17 has a flared mouth portion 15, the bottom of which is below the fibre collecting groove 8 and is provided with a lower surface 16, which extends upwardly and outwardly and which forms a continuation of the surface of the mouth portion 15. The lower surface 16 is generally parallel to the inner surface of lower portion 7 of the spinning rotor l and is adjacent thereto. The separator flange 17 has a frusto-conical upper surface 18 which confronts and lies parallel to the bottom surface 12 of the closure member 9 and extends downwardly and outwardly to converge with the lower surface 16 at a position adjacent the fibre collecting groove 8. Preferably, the point of convergence of these two surfaces is slightly above the level of maximum diameter of the fibre collecting groove 8. A plurality of grooves 19 is provided in a throat portion 20 of the passage 14 where the mouth portion 15 runs into the yarn passage 14.

In operation, fibres are fed from a known type of fibre opening system (not shown) in discrete form down the fibre feed duct 11 under the action of an airstream derived from the suction applied to the suction duct 5. The fibres emerge from the fibre feed duct 11 into the region between the bottom surface 12 of the closure member 9 and the upper surface 18 of the flange l7 and due to the high rotational speed of the spinning rotor l are collected as a ring of fibres in the fibre collecting groove 8 at the region of maximum diameter.

The fibres are removed from the fibre collecting groove 8 by twisting them into a tail end of a spun yarn 21 which is continuously withdrawn from the spinning rotor 1 through the yarn passage 14 by means of a pair of delivery rollers (not shown). It will be seen that the separator flange 17 serves to separate the incoming fibres from the outgoing yarn and that the fibres being spun into yarn, on leaving the fibre collecting groove 8, are controlled by the lower surface 16 of the separator flange 17 which serves to guide them as they pass from the fibre collecting groove 8 to the yarn passage 14, whilst deflecting the newly formed yarn below the fibre collecting groove 8.

To clear the spinning rotor l of fibrous material, the drive to the rotor is disengaged and the rotor allowed to reduce speed. The suction in the suction duct 5 is maintained and becomes effective to purge the rotor of fibrous material. In this connection, apparatus according to the present invention has been found to have improved self-clearing characteristics.

The embodiment of the invention illustrated in FIG. 2 is identical to that shown in FIG. 1 with the exception delivery tube is coaxial with the ning rotor.

guide surface, thereof, is spaced from the inner surface of the rotor adjacent thereto by a substantially constant gap.

What we claim as our invention and desire to secure by Letters Patent is: 5

1. Open-end spinning apparatus comprising:

a spinning rotor having an open end and an inner surface which is concentric with respect to the rotary axis of the rotor and which has two portions coverging toward a region of maximum diameter to form a fiber collecting surface,

a closure member for closing the open end of the rotor and having a closure surface in the region of the open end of the spinning rotor,

a fiber feed duct passing through said closure member for feeding fibers in discrete form to said rotor and having an exit opening in said closure surface, and

a yarn delivery tube passing through said closure member, extending from a yarn outlet end through the open end of the rotor and across a plane in which lie the points of maximum diameter of the fiber collecting surface and terminating at a yarn inlet end within the spinning rotor, said yarn delivery tube having a flange portion provided at said 2 5 yarn inlet end, said flange portion having a front guide surface which extends outwardly and back toward the fiber collecting surface to guide fibers being spun into yarn while being withdrawn from the fiber collecting surface and a rear surface opposite said front guide surface and confronting said closure surface and said fiber feed duct exit openmg.

2. Apparatus according to claim 1, wherein the yarn rotary axis of the spin- 3. Apparatus according to claim 2, wherein the front over a predetermined portion at least 4. Apparatus according to claim 3, wherein the front guide surface is of frusto-conical form over said predetermined portion thereof.

5. Apparatus according to claim 2, wherein the yarn delivery tube at the yarn inlet end has a flared throat portion leading to said front guide surface.

6. Apparatus according to claim 5, wherein the throat portion is provided with a plurality of grooves.

7. Apparatus according to claim 2, wherein said fibre collecting surface is formed by a localised fibre collecting groove. 4

8. Apparatus according to claim 7, wherein the said two portions of the inner surface of the rotor comprise a frusto-conical first portion extending away from one end of the rotor and outwardly from the rotary axis of the rotor and a frusto-conical second portion extending away from the other end of the rotor and outwardly from the rotary axis of the rotor and wherein the frustoconical first and second portions converge to said region of maximum diameter at which said localised fibre collecting groove is formed.

9. Apparatus according to claim 2, wherein the said rear surface of the flange portion and said front guide surface converge to form a circular edge of the flange portion.

10. Apparatus according to claim 9, wherein the said circular edge lies in a plane closer to the open end of the spinning rotor than the plane in which lie the points of maximum diameter of the fibre collecting surface.

11. Apparatus according to claim 2, wherein the said rear surface of the flange portion is of frusto-conical form, extending forwardly and radially outwardly from the rotor axis of the spinning rotor.

12. Apparatus according to claim 11, wherein said closure surface is of frusto-conical form and parallel to the frusto-conical rear surface of the flange portion.

13. Apparatus according to claim 11, wherein said closure surface is flat and lies in a plane at right angles to the rotary axis of' the spinning rotor.

14. Apparatus according to claim 2, wherein said rear surface of the flange portion and the said closure surface are such as to provide therebetween a constant gap. 

1. Open-end spinning apparatus comprising: a spinning rotor having an open end and an inner surface which is concentric with respect to the rotary axis of the rotor and which has two portions coverging toward a region of maximum diameter to form a fiber collecting surface, a closure member for closing the open end of the rotor and having a closure surface in the region of the open end of the spinning rotor, a fiber feed duct passing through said closure member for feeding fibers in discrete form to said rotor and having an exit opening in said closure surface, and a yarn delivery tube passing through said closure member, extending from a yarn outlet end through the open end of the rotor and across a plane in which lie the points of maximum diameter of the fiber collecting surface and terminating at a yarn inlet end within the spinning rotor, said yarn delivery tube having a flange portion provided at said yarn inlet end, said flange portion having a front guide surface which extends outwardly and back toward the fiber collecting surface to guide fibers being spun into yarn while being withdrawn from the fiber collecting surface and a rear surface opposite said front guide surface and confronting said closure surface and said fiber feed duct exit opening.
 2. Apparatus according to claim 1, wherein the yarn delivery tube is coaxial with the rotary axis of the spinning rotor.
 3. Apparatus according to claim 2, wherein the front guide surface, over a predetermined portion at least thereof, is spaced from the inner surface of the rotor adjacent thereto by a substantially constant gap.
 4. Apparatus according to claim 3, wherein the front guide surface is of frusto-conical form over said predetermined portion thereof.
 5. Apparatus according to claim 2, wherein the yarn delivery tube at the yarn inlet end has a flared throat portion leading to said front guide surface.
 6. Apparatus according to claim 5, wherein the throat portion is provided with a plurality of grooves.
 7. Apparatus according to claim 2, wherein said fibre collecting surface is formed by a localised fibre collecting groove.
 8. Apparatus according to claim 7, wherein the said two portions of the inner surface of the rotor comprise a frusto-conical first portion extending away from one end of the rotor and outwardly from the rotary axis of the rotor and a frusto-conical second portion extending away from the other end of the rotor and outwardly from the rotary axis of the rotor and wherein the frusto-conical first and second portions converge to said region of maximum diameter at which said localised fibre collecting groove is formed.
 9. Apparatus according to claim 2, wherein the said rear surface of the flange portion and said front guide surface converge to form a circular edge of the flange portion.
 10. Apparatus according to claim 9, wherein the said circular edge lies in a plane closer to the open end of the spinning rotor than the plane in which lie the points of maximum diameter of the fibre collecting surface.
 11. Apparatus according to claim 2, wherein the said rear surface of the flange portion is of frusto-conical form, extending forwardly and radially outwardly from the rotor axis of the spinning rotor.
 12. Apparatus according to claim 11, wherein said closure surface is of frusto-conical form and parallel to the frusto-conical rear sUrface of the flange portion.
 13. Apparatus according to claim 11, wherein said closure surface is flat and lies in a plane at right angles to the rotary axis of the spinning rotor.
 14. Apparatus according to claim 2, wherein said rear surface of the flange portion and the said closure surface are such as to provide therebetween a constant gap. 